Device to regulate the depth of gasoline in the float chambers of carburetors



Feb. 8, 1944. GILBERT 2,340,876

L. W. DEVICE TO REGULATE THE DEPTH OF GASOLINE IN THE FLOAT CHAMBER OF THE CARBURETOR Filed June 13, 1942 2 Sheets-Sheet l 7 7 6 6X 8 6 as 8 so I T 7 H A\\\\\ I! I so 5%- x [1/]: I IO 4 .illllllllprl INVENTOR.

ISY

Feb. 8, 1944.

L. w. GILBERT 2,340,876 DEVICE TO REGULATE THE DEPTH 0F GASOLINE IN THE FLOAT CHAMBER OF THE CARBURETOR Filed June 13, 1942 2 SheQtS-Sheet 2 INVENTOR.

L @WILS Gi/berf M ATT RNEY.

Patented Feb. 8, 1944 DEVICE TO REGULATE THE DEPTH F GAS- OLINE IN THE FLOAT CHAMBERS 0F CAR- BURETORS Lewis W. Gilbert, Bradford, Pa., assignorto Frank Keiper, Rochester, and NoraEvelynBaylisGilbert, Seneca FallsgN. Y.

. Application June .13, 1942, Serial No.,:4%l6,9[i8 19 Claims. (01. 123-119) The object of this invention is to produce a device that will regulate the depth of gasoline in the float chamber of the carburetor so as to savegasoline and get out of the gasoline more miles per gallon.

Another object of the invention is to provide a regulating device that will permit the car to get started with the normal level of gasoline in,

the carburetor which level will remain normal until the motor warms upand then the level will be automatically lowered to a predetermined level for ahigher mileage per-gallon of gasoline.

'Another object of the invention is to provide means that will hold the-gasoline at normal level.

on the line larl.r-of Figure 4 showing'the piston in its lowest position.

Figure 2-is a-vertical section on the line l x-la: of Figure 4 showing the piston in its highest position.

Figure 3 is a sideelevation of the device viewed from the rear of-Fig-ure-l.

Figure 4 is a top plan view oi thewhole device shown in Figure 1.

Figure 5 is a horizontal section on the line 5:1:-5:1: of Figure '1. I

Figure-6 is a horizontal section on the-line 650-61; of Figure 2, the spring-being omitted from the thermostatic chamber.

Figure '7 is a vertical section through the float chamber oi the carburetor showing the regulating device superimposed thereon, the gasoline being shown at its normal level.

Figure 7a is a detail view showing the housing I30 attached to the outside of the motor.

Figure 8 shows-a-vertica1-section through'the float chamber of the carburetor with the regulating device superimposed thereon, the-gasoline being shown at the lower .levehwhich level is secured by achange in position of the regulating parts. 1

Figure 9 is a perspective-view of thewedge 1B.

Figure 10 is a sectional view of. a modified form of cylinder and piston in which .the cylinder is-shown openat the bottom, the downwarc1 movement of the piston being limited by a wire extending upwardly therefrom.

Figure 11 is a sectional view of a modifiedior n, of the cylinder and piston in which a trunk pis ton is shown having three diameters.

Inthe drawings, like numeralsindicate like parts.

In-thedrawings reference I indicates a cylinder having apiston 2 therein to Which piston isattached the stem 3 at the bottom thereof and a stem 4 at the topthereof. This piston is capable of movement up and down in the cylinder being moved up in:r.espons e to a, vacuum developed in the cylinder above the piston and be ing normally held down .bya spring 5 whichis contained in thecyli-nder. The top of the cyl-;

- vinder is closed by a screw plug 6 .in which is,

provided an opening 1 which'vextends up to near the top oi -the plugand then opens laterally. The plug 6 acts as a stop forthe piston. Ase-- called straight elbow. maybe used ior this pur; pose. A tube.-:8.is'threaded into this openi l qto provide a simple. andeasy manner of;connecting the tube to the intake manifold so that the vacuum produced therein while the engine is running will raise-:tlle piston andcompressthe spring.

When theengine is cold oruntil theengine heats up the .piston v271s mechanically held against" being raised by a lockpin .9, the position of which is controlled .by a thermostat spring lilf carried in-thechamberor housi g. v

L'I'he thermostat housing or; the chamber l l; is,

connectedto the inside of the cylinder Lby a tube l2 in which the loclgpin a loosely fits. When the engine starts a vacuumis produced in the intake manifold and this in turn-producese vacuum in the cylinder, l and draws air through the tube it past the pin;9. Theair flows-from the housing of the thermostat chamber 1 I. {I fhe pin l .is-shown inFigure 5 formed with a loop 9min which the thermostat spring it) engages. This loop 9a engageswith the tube 52 andpre vents .the pin vfrom being pushed into the cylin der' too .far bythe thermostat spring. Extending from. this chamber or housing -'ll ;is.a

- I3 that extends to some hot spot on the motor oronthe. exhaust manifold, .Untilthe en e or the .1 exhaustumanif old heats up, cold air w ll be drawnithrough "this tube; I13 and; throughthe tube-12; into the intake manifold and as long as this condition..exists the. lockpin 9 will engage the topuof ."the .piston .;2 ;and ,iplfevelli "i from rising; in:;response 1:1?0 the vacuum. Except-for the tubular. openings :the thermostat ehamber iis seale'dl upibeing closed' encore-eld vth e plate :I lda'having a: layer e15 leather interposed between the housing II and the plate II a so as to make a joint that is substantially air tight. But as soon as the hot spot on the motor or the exhaust manifold heats up, the warm air drawn in through the tube l3 will gradually cause the thermostat spring I to flex and will draw the lockpin 9 to the right as shown in Figure 2, thus releasing the piston 2 which can then rise in response to the urge of the vacuum. The movement of the thermostat spring [0 to the right in Figure 2 is limited by the shape of the housing.

The opening I is larger and will pass more air than will the clearance in the tube l2 around the pin 9. Consequently the vacuum in the cylinder I will be greater than the vacuum in the ure 7a the housing [30 is attached to the outside of the motor I3b and the tube 8 is shown connected to the intake manifold 40 of the engine. This housing is closed on all sides but and and is fastened to the engine or manifold so as to cover: the hot spot. It helps the heating of the thermostat chamber H and will be great enough to raise the piston and compress the spring 5. When the piston 2 rises it will partly or wholly close the opening in the tube l2, thus causing the vacuum in the cylinder l to act with extra force in raising the piston 2.

To permit-'air to enter the cylinder below the piston the stem 3 can be made with a loose fit, in the cylinder head M with which it makes engagement or an opening I5 can be provided through the side of the cylinder l at or near the bottom of the'cylinder.

In this way the piston 2 can be made to raise and compress the spring 5 whenever there is a suflicient vacuum developed in the intake manifold.

To regulate the level of the gasoline .in the float chamber l5a, I provide wedge 16 connected to the stem 3 below the piston. The wedge is in the form of an angle-shaped bracket which is loosely fastened to the bottom on the stem 3 by the screw l'l andit is held loosely thereonso that it can rock back and forth with a floating motion as it adjusts itself between the head of the needle valve 24 and the end of the arm 22 on the float 22a.

The cylinder shown in Figure 1 is provided at the lower end with a flange l8 and a reduced end [4. An opening is provided in the top of the float chamber of the carburetor. in which this reduced end makes a snug flt. A strap or plate 2| is provided having an opening therein that fits around the cylinder 1 and this 'strap 2| is fastenedto the top of. the float chamber |5a of the carburetor by a screw not shownor in any other suitable manner. The strap is shown in full lines in Figure 1 at the left of the device, it being understood that its normal position would ordinarily be back of the cylinder and concealed thereby as shown in. Figure 7. The stem 3 with the wedge l6 extends down into the float chamber, the wedge being interposedbetween the end of the float arm 22, and the needle valve 24. When the motor is cold the parts will be held in the position shown in Figure 7 by the lock pin 9 in which the thin part of the wedge I6 is interposed between the end of the float arm 22 and the end of the float needle valve 24.

While the parts are in this position the float takes the position shown in Figure 7, this being the normal level of gasoline in the corburetor as recommended by the corburetor manufacturers.

-When-the engine starts this level will be maintained until the hot spot has become heated up and until the thermostat spring Ill has pulled the lockpin 9 to the right as in Figure 2. Then the vacuum of theintake manifold can raise the.

piston 2 and inso doing it will raise the wedge 'It will be understood that the exhaust manifold heats up quicker than the motor generally and its cooling water heats up. It is desirable to delay the operation of the thermostat until the motor generally has warmed up rather than have the thermostat operate as soon as the ex-- seasonal variation in the temperature of the air or in response to variations in temperature in the float chamber of the carburetor which includes variations in the temperature of the gasoline. ,It will also be understood that when the engine starts to run its temperature goes up much faster and much higher than does the temperature of the float chamber of the carburetor which is kept rather cool-by the vaporization of the gasoline and goes up much slower than does the temperature of the exhaust manifold.

When the car ,is going up hill and the vacuum drops due to a hard pull on the engine, the spring 5 can push the piston down until the thin part of the wedge has been exposed between the needle valve 24 and the arm 22 of the float. This will permit the needle valve to move to the left to permit more gas to flow into the float chamber until the float rises to close the needle valve at the normal gasoline level. This cycle will'also occur when the driversteps on the accelerator pedal for quick acceleration on the motor and when the vacuum of the intake manifold rises again, then the wedge l6 will rise and close the needle valve until the level of the-gasoline in the float chamber has been lowered.

The thermostat housing II is fastened to the cylinder in the manner that will now be described. g Fastened to one side of the thermostat chamber is a short strap 26 and fastened to the other side of the chamber is a long strap 21. The

plate 32 having an arcuate slot 3 3therein into which extends a stud 34 havinganut 35 on the tened'in this slot is the inner end of the helicalthermostat spring Hi, the outer end of which is connected to the lockpin 9. By turning the elbow to any desired position as shown in Figure 3 any desired tension can be thrown'on this spring thatwill hold the lockpin 9 in the position shown in Figure 1 as long as the engine is cold or until the hot spot has heated up.

On the inside of the thermostat housing H is placed a washer 38 which is-threaded on the inner end of the elbow 3| therebyholding the elbow in place so that it can turn in the thermostat housing to secure the proper adjustment of the spring ID as above described. This elbow is provided with an opening 39 which extends through it as-shownin Figure 6, so that hot air can be drawn through the elbow into the thermostat housing H.

In Figure 10 I have shown a modified form of the cylinder in which 58 indicates the cylinder and 5| indicates the piston, it being understood that the bottom of the cylinder is open. An elbow 52 is provided on top of the cylinder by which it is connected to the intake manifold. The piston is normally held down by the spring 53 and the limit of its downward movement is fixed by a rod or wire 54 having an enlarged end 55 at the top, which passes up through the elbow. The upward movement of the piston is controlled by a lockpin similar to the pin 9 shown in Figure l and-the lower end of the piston-has a stem 55 thereon on which is carried the wedge 16 as is shown in Figure 1 and operates to control the gas supply as shown in Figures '7 and 8. A stem 51 is also provided on top of the piston 5| to which the rod or wire 54 is attached and on which the spring 53 is centered.

It will'also be understood that this device can be made as an integral part of thecarburetor as well as made and sold as an accessory thereto.

In Figure 11 I have shown a trunk piston in the cylinder. The piston has three diameters. The intermediate diameter is provided so that an air passage will always be open between the thermostat housing II and the cylinder I through the tube l2, so that'the air will circulate from the hot spot on the motor through the opening I in the plug 6, when the piston is in its raised position, as well as when the piston is in its slowest position tube l2 and the opening I in the plug 6. The smallest diameter is to make room'ior the spring 5.

As shown in Figures 1 and 2 the bottom of plug 6 is grooved as indicated at 7a to provide an air passage when the piston is in contact with the plug.

In Figure 10 the corresponding groove is on top of the piston.

It will also be understood that the terms of normal level and high level and low level of gasoline in the float chamber of thecarburetor include the actual levels of gasoline as the level fluctuates slightlywhen it permits the float to move down to open the valve and causes it to move up to close the valve at or about either of these levels.

I claim:

1. In a device to regulate the depth of gasoline in the floatchamber of a carburetor, means formai-ntainingthe gasolineat a standard level g while the engine iswarming up, said means operating to shut off the inflow of --gasoline inthe float chamber after the engine is warmed up until the level of gasoline in the float chamber has been substantially reduced, said means then holding the gasoline at the reduced level while the engine runs, said means'incl'uding a thermostat control-device located outside the carburetor and warmed by an air current heated by contact with the outside of the engine.

2. In a device to regulate the depth'of gasoline in the float chamber of acarburetor means for maintaining the gasoline at a standard level while the engineis warming up, said means operating to shut off the inflow of gasoline in the float chamber after the engine is warmed up until the level of gasoline in the float chamber has'been substantially reduced, said means-then holding the gasoline atthe reduced level while the engine runs, said means'including a vacuum control connected to the intake manifold and a thermostat controlled by warm air taken from a hot part of the engine and the parts being-so connected that the warm air passes through the vacuum control and into the intake manifold.

3. In a device to regulate the depth of gasoline in the float chamber of a carburetor, afloat and a valve for maintaining the gasoline ata standard level, a regulating device that will depress the float and hold the valve closed-until the level-of gasoline in the float chamber is sensibly reduced, said regulating comprising a-connection between the intake manifold of the engine and a hot spot that will draw a current of air through-the-regulating device while the engine is running-without depressing the float and will cause the float to be depressed and the valve to be closed after the air passing through the regulating device has become sufliciently warmed up. i

4. 'In a device to regulate the depth of gasoline in the float chamber of a carburetor, afloat-and a valve for maintaining the gasoline at a standard level, a regulating device that will depress the float and hold the valve closed until the level of gasoline in the float chamber is sensibly reduced,

said regulating device comprising a connection between the intake manifold of the engine and a hot spot that will draw a current of air through the regulating device while the engine is running without depressing the float, and will cause the float to be depressed after the air passing through the regulating device has become sufiiciently warmed up, a thermostat afiected by said warm air, a piston held against movement by said thermostat until the air becomes warm enough to cause it to release the piston, the vacuum of the intake manifold then causing the piston to move and depress the float and hold it indepressed position with the valve closed.

5. A carburetor having a needle valve, a float chamber and a float and a float arm, said float and float arm being adapted to hold the needle valve closed, when the gasoline reaches a standard level in the float chamber, a wedge, regulating means for interposing said wedge between the float arm'and the needle valve and holding it closed until the gasoline had dropped to a lower level in the float chamber, said means operating to lower the level of the gasoline in the float chamber only after the engine is operating and warmed up, said means comprising a tubular connection between the intake manifold of the engine and a hot spot that will draw a current of warm air through the regulating means, a thermostat' in said regulating means, a piston held against movement by the thermostat, saidther mostat being moved by the warm; air to release the piston, a vacuum for causing the piston to move the wedge between the float arm and the for maintaining thelevel of thega oline at a high level when the engine is idle, and during the warming up period of the-running of the engine, a regulating device operating to lower the level of the gasoline in the float chamber after the engine is warmed up and hold it at the lower level, said regulating device comprising a connection between the intake manifold of the engine and a hot spot that will draw a current of warm air through the regulating device and at a partial vacuum through a part of the regulating device while the engine is running after it has warmed up and will maintain a partial vacuum in a part of the regulating device while the engine running.

7. In a device to regulate the depth of gasoline in the float chamber of a carburetor means for maintaining the gasoline at a standard level while the engine is warming up, said means operating to shut 01f the inflow of gasoline in the float chamber after the engine is warmed up until the level of gasoline in the float chamber has been substantially reduced, said means then holding the valve closed while the gasoline is above the reduced level while the engine runs, said means comprising a float, a float arm and a needle valve, a wedge having a thick part and a thin part, the thin part being normally interposed between the float arm and the needle valve when the engine is cold, means for moving the wedge so as to draw the thick part of the wedge between the float arm and the needle valve after the engine warms up thereby causing the float to close the needle valve when the gasoline in the float chamber is at a lower level.

8. In a device for regulating the depth of gasoline in the float chamber of a carburetor, the combination of a float chamber, a float and a float arm and a needle valve closed thereby when the gasoline in the float chamber is at a standard level, a wedge and means for interposing the wedge between the float arm and the needle valve and holding it closed until the gasoline has dropped to a lower level said wedge and float then permitting the valve to open and to permit gasoline to flow into the float chamber to main tain the low level.

9. In a device for regulating the depth of gasoline in the float chamber of a carburetor, the

combination of a float chamber, a float, a float arm and a needle valve closed thereby when the gasoline is at a high level, a regulating device that causes the float and its arm to close the needle valve until the gasoline is at a low level in the float chamber, said device comprising a Wedge interposed between the needle valve and the float arm, and a piston for moving the wedge, said piston and Wedge being held against movementby warming up period of the running of the engine,

a regulating device operating to lower the level of the gasoline in the float chamber after the engine is warmed up and hold it at the lowerv level, said regulating device comprising a connection between the intake manifold of the engine and a hot spot that will draw-a current of warm air through the regulating device and at a partial vacuum through a part of the regulating device while the engine is running after it has warmed up and will maintain a partial vacuum in a part of the regulating device while the engine is running.

11. In a device to regulate the depth of gasoline in the float chamber of a carburetor, means for maintaining the gasoline at a standard level while the engine is warming up, said means operholding the gasoline at the reduced level while the engin runs, said means comprising a float, a float arm and a needle valve, a wedge interposed between the float arm and the needle valve, said wedge having a thick part and a thin part, the thin part being normally interposed between the float arm and the needle valve when the engine is cold, means for moving the wedge so as to draw the thick part of the wedge between the float arm and the needle valve after the engine warms up, the thick part of the wedge and the float operating to hold the needle valve closed when the gasoline in the float chamber is at low level the thin part of the wedge and the float operating to hold the needle valve closed when the gasoline is at a high level in the float chamber.

12. In a device to regulate the depth of gasoline in the float chamber of a carburetor means for maintaining the gasoline at a standard level while the engine is warming up, said means operating to shut oil the inflow of gasoline in the float chamber after the engine is warmed up until the level of gasoline in the float chamber has been substantially reduced, said means then holding the gasoline at the reduced level while the engine runs, said means comprising a float, a float arm and a needle valve, a wedge interposed between the float arm and the needle valve, said wedge having a thick part and a thin part, the thin part being normally interposed between the float arm and the needle valve when the engine is cold or idle, a cylinder and a piston, said cylinder being connected to the intake manifold so that the piston will be moved by the vacuum created therein, a thermostat spring normally holding the piston against movement when the engine is cold, a housing in which said thermostat spring is enclosed, said housing being connected on one side to a hot spot on the engine or exhaust manifold, and

being connected on the other side to the cylin-- --13.- In;a device for regulating the depth of gasolineinthe float chamber ofa carburetor, V

the combination of a float chamber, a float, a float arm and a needle valve closed thereby when the gasoline is at a high level, a'regulating device that causes the float and its arm to close the needle valve when the gasoline is at a low level in the float chamber, said device comprising a wedge interposed between the needle valve and the float arm and a piston for moving the wedge, said piston and wedge being held against move ment by a thermostat, said piston being released from said thermostat by a current of warm air, a vacuum for drawing the current of warm air and moving the piston and wedge after the piston has been released from the thermostat, a spring for returning the piston and Wedge to normal position on the failure of the vacuum.

14. A carburetor for internal combustion engines comprising, in combination, a fuel chamber for the carburetor; and means including a thermostatic element for controlling the admission of fuel to said chamber, said thermostatic element being located outside of the carburetor and being warmed by air heated by the engine.

15. A carburetor for internal combustion engines comprising, in combination, a fuel chamber having a fuel admission port, a valve for controlling the port; and means including a thermostatic element for controlling the valve, said thermostatic element being located outside of the carburetor and being warmed by air heated by the engine.

16. A carburetor for internal combustion engines comprising, in combination, a fuel chamber having a fuel admission port; a valve for controlling said port; a float in said fuel chamber; and means including a thermostatic element operatively connecting the valve with the float for controlling the valve, said thermostatic element being located outside of the carburetor and being warmed by air heated by the engine.

17. An internal combustion engine comprising, in combination, a carburetor, having a passageway in communication with the engine; a fuel chamber for the carburetor adapted to contain a quantity of fuel; a fuel nozzle extending below the level of fuel in the chamber and leading to said passageway in communication with the engine; and means including a thermostatic element for varying the level of fuel in the fuel chamber, said thermostatic element being located outside of the carburetor and being warmed by air heated by the engine.

18. In a device to regulate the depth of gasoline in the float chamber of a carburetor means for maintaining the gasoline at a standard level while the engine is warming up, said means operating to shut off the inflow of gasoline in the float chamber after the engine is warmed, up until the level of gasoline in the float chamber has been substantially reduced, said means then holding the gasoline at the reduced level while the engine runs, said means including a vacuum control connected to the intake manifold.

19. In a device for regulating the depth of gasoline in the float chamber of a carburetor, the combination of a float chamber, a float and a float arm and a needle valve closed thereby when the gasoline in the float chamber is at a standard level, means operated by the Vacuum of the intake manifold for reducing the level of the gasoline in the float chamber to a level lower than the standard level after the engine is in operation, said means being controlled by a thermostat located outside the carburetor and heated by the engine.

LEWIS W. GILBERT. 

